PSI - Issue 52

Angela Russo et al. / Procedia Structural Integrity 52 (2024) 535–542 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

540

6

3.2. SS#2 configuration For the SS#2 configuration, characterized by an initial damage of 120 mm, the results of the load and evolution of the delaminated area as a function of the displacement are reported in Figure 7. According to the figure, the behaviour of this configuration differs from the previously shown SS#1 configuration. Indeed, by increasing the initial damage length the maximum load reached by the panel decreases (as clearly perceptible in the load-displacement curve in Figure 7). Moreover, the delamination exhibits a more gradual and stable propagation.

Load-Displacement

Delaminated area-Displacement

10 15 20 25 30 35

10000 12000 14000 16000 18000

0 2000 4000 6000 8000

SS#2

SS#2

Load [kN]

0 5

Delaminated area [mm2]

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

Displacement [mm]

Displacement [mm]

Figure 7. Results of the SS#2 configuration

In this case, a damage initiation load equal to 27.83 kN has been found. Figure 8 shows the debonding condition at the delamination onset step and at the last step and the buckling behaviour of the panel at the same displacement value. Again, the simulation has been terminated by the user as the delamination length exceed a value 100% greater than the initial delamination length value. According to the figure, the delamination onset is anticipated with respect to the SS#1 configuration. Indeed, the local buckling of delamination arises at 0.40 mm, as has been found by linear eigenvalue buckling analysis, versus the 0.42 mm of the SS#1 configuration.

0.51 mm 27.83 kN

0.75 mm 41.79 kN 1.45mm 30.03 kN

-12.37

-7.61

-2.85

1.91

6.67

-1.85

-1.85

-1.35

-.847

-.348

-14.75

-9.99

-5.23

-4.69

4.29

-2.10

-1.60

-1.10

-.598

-.099

Figure 8. Initial and final debonding – SS#2 configuration